Chapter 17 Study Guide Flashcards

1
Q

What are the four principal mechanisms of communication between cells? Describe them

A

1) Gap junctions: Allow molecules, nutrients, and electrolytes to move from cell to cell
2) Neurotransmitters: Released from presynaptic neurons to postsynaptic neurons
3) Paracrines: Secreted into tissue fluids to affect nearby cells
4) Hormones: Chemical messengers that travel in the bloodstream to other tissues and organs

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2
Q

The endocrine system consists of glands, tissues and cells that secrete what? Define endocrinology

A

1) Hormones
2) Endocrinology: the study of the endocrine system and the diagnosis and treatment of its disorders

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3
Q

What properties does a hormone have? (3)
What are some endocrine glands?

A

1) Properties:
a) They’re chemical messengers
b) They’re transported by the bloodstream.
c) They stimulate physiological responses in target cells
2) Examples of endocrine glands include the thyroid, pituitary gland, hypothalamus, and pancreas.

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4
Q

How do exocrine and endocrine glands secrete their products? Which has external secretions; which have internal secretions?

A

1) Exocrine glands use ducts, endocrine glands do not.
2) Exocrine glands have external secretions, whereas endocrine glands have internal secretions.

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5
Q

What are examples of exocrine secretions? What are examples of endocrine secretions?

A

1) Examples of exocrine secretions include sweat, tears, digestive juices, and saliva
2) Examples of endocrine secretions include the secretion of hormones (ADH, FSH, OT, ACTH, GH, etc)

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6
Q

1) In comparing the nervous system to the endocrine system, what is something they have in common regarding specificity, receptors, and communication?
2) Both neurotransmitters and hormones depend on target cells to provide what?

A

1) Both rely on their targets having receptors, both serve for internal communication, several chemicals act as both hormones and neurotransmitters, and both systems can have a similar effect on target cells.
2) The targets of the nervous and endocrine systems (the postsynaptic neuron and target organ/cells respectively) both must have receptors.

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7
Q

1) In comparing the nervous system to the endocrine system, what is different regarding speed and persistence of response
2) How are they similar in adaptation to long-term stimuli and area of effect?
3) Is one more focused on a particular organ or limited number of cells or does one have a more widespread effect?

A

1) The nervous system has a quicker but more short-lived response than the endocrine system; it may take the endocrine system seconds or days to respond, but the effect can last for days or longer.
2) The nervous system adapts quickly to long-term stimuli and the response declines, whereas the endocrine system adapts more slowly and response persists.
3) The nervous system is targeted and specific (one organ) whereas the endocrine system is general and widespread (many organs)

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8
Q

1) Give 3 examples of chemicals that function both as neurotransmitters and hormones.
2) Some hormones and neurotransmitters produce identical effects on the same targets, can you think of an example?

A

1) Norepinephrine, dopamine, and ADH
2) Norepinephrine and glucagon both cause glycogen hydrolysis in liver

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9
Q

1) How does the nervous and endocrine systems regulate each other?

A

1) Neurotransmitters can affect glands, and hormones can affect neurons

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10
Q

1) Where is the location of the hypothalamus?
2) List some of the primitive functions it regulates.
3) How is the pituitary gland connected to the hypothalamus, what is the name of the stalk?
4) The pituitary gland is housed in a depression of which bone and its bone marking?

A

1) The hypothalamus is above the pituitary gland in the brain
2) Water balance, thermoregulation, sex drive, childbirth
3) The pituitary gland is connected by the stalk called the infundibulum.
4) The pituitary gland is housed in the sella turcica of the sphenoid bone.

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11
Q

Which structure of the pituitary has no nervous connection to the hypothalamus? How is it linked to it then?

A

The anterior pituitary is connected to the hypothalamus by the hypophyseal portal system.

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12
Q

What does the hypophyseal portal system consist of, and where are these things located?

A

The primary capillary bed in the hypothalamus and the secondary capillary bed in the anterior pituitary.

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13
Q

How many hormones (by number) are released by the hypothalamus that regulate the anterior pituitary? Of that number, how many stimulate release and how many inhibit release?

A

6 hormones; 4 stimulate and 2 inhibit (PIH and somatostatin)

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14
Q

1) Can you list the 6 hormones released by the anterior pituitary?
2) Can you list the 6 hypothalamic hormones that control the hormones released from the anterior pituitary?

A

1) FSH, LH, ACTH, TSH (FLAT) are the tropic hormones; PRL and GH (PiG) are non-tropic.
2) TRH, CRH, GnRH, and GHRH promote secretion; PIH and somatostatin inhibit.

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15
Q

1) The posterior pituitary constitutes the posterior one-quarter of the pituitary. How does the hypothalamus connect with it?
2) What are the names of the two hormones stored here?
3) What causes the hormones stored in the posterior pituitary to be released?

A

1) The hypothalamo-hypophyseal tract (nerves).
2) ADH and OT are stored in the posterior pituitary.
3) They’re released by an action potential moving down the nerve

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16
Q

1) In summary, how many total hormones are released by the hypothalamus?
2) How many regulate the anterior pituitary?
3) Of the hormones in the posterior pituitary, how many were produced by the posterior pituitary?

A

1) There are 8 hypothalamic hormones
2) 6 regulate the anterior pituitary.
3) Neither of the 2 hormones stored in the posterior pituitary were produced there.

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17
Q

1) What does FSH target?
2) What does LH stimulate in females? In males?
3) What hypothalamic hormone stimulates release of FSH and LH?

A

1) The gonads
2) In females it stimulates ovulation, stimulates corpus luteum to secrete progesterone. In males it stimulates testes to secrete testosterone
3) GnRH releases FSH and LH

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18
Q

1) TSH stands for what?
2) What organ does TSH target, and what hormone is stimulated to be released?
3) What hypothalamic hormone stimulates release of TSH; what hypothalamic hormone inhibits release of TSH?

A

1) Thyroid stimulating hormone.
2) Targets the thyroid to release thyroid hormone.
3) TRH stimulates the release of TSH, somatostatin inhibits the release of TSH.

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19
Q

1) ACTH stands for what?
2) What specific part of an organ does ACTH target, and what hormone is stimulated to be released?
3) What hypothalamic hormone stimulates release of ACTH?

A

1)Adrenocorticotropic hormone
2) It stimulates the adrenal cortex to secrete glucocorticoid.
3) Corticotropin-releasing hormone (CRH) stimulates its release.

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20
Q

1) What does PRL stand for?
2) What organ does PRL target, and what is stimulated to be released?
3) What hypothalamic hormone stimulates release of PRL; what hypothalamic hormone inhibits release of PRL?

A

1) PRL stands for prolactin.
2) Targets the mammary glands to produce milk.
3) TRH promotes the release of PRL; PIH inhibits the release of PRL.

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21
Q

1) What does GH stand for?
2) What does GH do?
3) What hypothalamic hormone stimulates release of GH; what hypothalamic hormone inhibits release of GH? Note that the hypothalamic hormone that inhibits release of GH, is the same that inhibits release of what other anterior pituitary hormone?

A

1) GH stands for growth hormone,
2) It primarily stimulates mitosis and cellular division; this increases blood glucose, lipid metabolism, and blood glucose levels.
3) GHRH stimulates its release and somatostatin inhibits its release (also inhibits the release of TSH).

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22
Q

1) What does ADH do? (hint… kidneys)?
2) Why is it also called vasopressin?
3) Hyposecretion results in what disorder? What is the classic symptom?

A

1) It increases water retention by the kidneys.
2) It’s also called vasopressin because it can cause vasoconstriction.
3) Diabetes insipidus, and its classic symptom is polyuria.

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23
Q

Oxytocin (OT) has a variety of reproductive functions ranging from intercourse to birth to breast-feeding. Can you give some examples of its functions?

A

1) A surge of OT is released during sexual arousal and orgasm; promotes feelings of sexual satisfaction and emotional bonding between partners. 2) Stimulates labor contractions during childbirth and stimulates flow of milk during lactation (both positive feedback mechanisms); may promote emotional bonding between lactating mother and infant

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24
Q

1) In times of stress, this triggers ACTH secretion, what does this lead to? 2) During pregnancy, this induces prolactin secretion. What does this do?
3) High osmolarity triggers release of ADH. What does this do?
4) Infant suckling triggers release of OT, which does what?
5) What organ controls rate of pituitary hormone secretions?

A

1) Stimulates adrenal cortex to secrete glucocorticoids
2) Causes the mammary glands to grow.
3) Increases fluid retention by the kidneys; decreases osmolarity
4) Stimulates flow of milk
5) The hypothalamus (and cerebral control)

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25
Q

1) Define negative feedback.
2) Using the pituitary–thyroid system, how would negative feedback inhibition occur? 3) Can you think of an example of where a hormone triggers a positive feedback cycle?

A

1) Negative feedback: increased target organ hormone levels inhibit release of hypothalamic and/or pituitary hormones
2) Higher levels of thyroid hormone inhibits release of TRH by hypothalamus and of TSH by anterior pituitary
3) Stretching of uterus increases OT release, causes contractions, causing more stretching of uterus, etc. until delivery

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26
Q

1) The pineal gland is located where?
2) The pineal gland’s function is somewhat mysterious; it may play a role in establishing ____________ rhythms of physiological function.
3) During the night it synthesizes what?

A

1) The pineal gland is located in the brain posterior to the hypothalamus.
2) Circadian
3) At night the pineal glad synthesizes melatonin.

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27
Q

The thymus is located where? What organ systems does it play a role in? It’s the site of maturation for what cells?

A

The thymus is located just above the ascending aorta, and it plays a role in the endocrine, lymphatic, and immune systems (maturation of T cells).

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28
Q

1) How does the thymus change in terms of size over the course of a person’s life?
2) What does it secrete?

A

1) The thymus shrinks/ undergoes involution after puberty.
2) It secretes thymopoietin, thymosin, and thymulin.

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29
Q

1) The thyroid is located where?
2) Thyroid follicles are filled with a protein-rich colloid and lined with a simple ____________ epithelium of follicular cells.
3) What does it secrete, and in response to what stimulus from the pituitary?

A

1) Located in the neck at an isthmus below the larynx.
2) simple cuboidal epithelium
3) It secretes T3 and T4 (thyroid hormone) in response to TSH.

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30
Q

1) What is the primary effect of TH?
2) What does TH do in terms of oxygen consumption? What does it do to the respiratory rate, heart rate and strength of the heartbeat? What about the appetite?

A

1) The primary effect of TH is increasing metabolism.
2) It also increases oxygen consumption, heat production, appetite, growth hormone secretion, alertness, reflex speed.

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31
Q

1) The thyroid gland also contains nests of C (clear) cells, or _______________ cells, between the follicles.
2) These cells secrete what? When/why do they secrete this? What do they decrease the level of?

A

1) parafollicular
2) They secrete calcitonin when blood calcium rises to decrease the blood calcium.

32
Q

In terms of thyroid disorders, explain what causes Grave’s disease, cretinism and myxedema

A

1) Graves disease: Thyroid hypersecretion due to autoantibodies mimicking the effect of TSH.
2) Cretinism: Congenital thyroid hyposecretion.
3) Myxedema: Adult thyroid hyposecretion.

33
Q

1) The parathyroid glands are located where? How many of them are there? 2) What do they secrete? They secrete this hormone in response to what being low? What do they increase the level of?

A

1) Located on the back of the thyroid gland, there’s usually 4 parathyroid glands.
2) They secrete parathyroid hormone in response to low blood calcium levels, and increase the level of calcium.

34
Q

In terms of parathyroid disorders, be able to explain hypoparathyroidism and hyperparathyroidism; what causes them and what do they do?

A

1) Hypoparathyroidism is often due to surgical excision during thyroid removal, causes fatal tetany (spasms in larynx) due to low blood calcium
2) Hyperparathyroidism is often due to a parathyroid tumor and promotes renal calculi formation and soft, deformed bones

35
Q

1) The outer region of the adrenal gland is known as? The inner region is known as?
2) The adrenal medulla has a dual nature, what does this mean?

A

1) The outer region is the cortex, the inner region is the medulla
2) It’s both an endocrine gland and a ganglion of the sympathetic nervous system

36
Q

1) What cell releases catecholamines and under what conditions are they usually released?
2) What are the two major catecholamines?

A

1) Chromaffin cells of the adrenal medulla, which are modified sympathetic postganglionic neurons release catecholamines into the bloodstream when stimulated.
2) Epinephrine and norepinephrine

37
Q

1) How does the adrenal medulla increase alertness and prepare the body for physical activity?
2) What does it have the liver do? 3) Why is epinephrine inhibiting insulin secretion?

A

1) The adrenal medulla mobilizes high-energy fuels, lactate, fatty acids, and glucose.
2) It mobilizes glucose by causing glycogenolysis and gluconeogenesis by liver
3) Epinephrine inhibits insulin secretion to keep the blood glucose levels higher for the brain to use.

38
Q

1) When the adrenal medulla is increasing blood flow to muscles, where would you decrease blood flow?
2) What about heart rate, BP and airflow; do you increase or decrease?

A

1) Decrease blood flow to the digestive system and urinary system.
2) Increase blood pressure, heart rate, pulmonary airflow, and metabolic rate

39
Q

1) What is the function of aldosterone? Will this increase or decrease blood volume and blood pressure?
2) What does it mean to be part of RAA?

A

1) Aldosterone promotes sodium retention and potassium secretion; this promotes higher blood volume and blood pressure.
2) It means it’s a part of the renin-angiotensin-aldosterone system.

40
Q

1) The adrenal cortex, has three categories of hormones. Glucocorticoids stimulate what?
2) These hormones have what type of effect on inflammation? What does excessive secretion suppress?

A

1) Glucocorticoids (i.e. cortisol) stimulate gluconeogenesis and fat and protein catabolism.
2) Glucocorticoids (i.e. cortisol) has an anti-inflammatory effect, but this becomes immune suppression with long-term use.

41
Q

What do the sex steroids release?

A

Androgens and estradiol

42
Q

In terms of adrenal disorders, be able to explain:
1) Cushing syndrome
2) Adrenogenital syndrome (AGS), 3) Addison’s disease, including symptoms

A

1) Cushing syndrome: Cortisol hypersecretion.
a) Symptoms: Hyperglycemia, hypertension, weakness, edema. Also causes rapid muscle and bone loss due to protein catabolism, and abnormal fat deposition (moon face and buffalo hump)
2) Adrenogenital syndrome (AGS): Adrenal androgen hypersecretion (accompanies Cushing)
a) Symptoms: causes enlarged external sexual organs in children and early puberty. Masculinizing effects on females.
3) Addison’s disease: Cortisol and/or aldosterone hyposecretion.
a) Symptoms: Hypoglycemia, hypotension, weakness, weight loss, and hyperpigmentation

43
Q

The pancreas located where? Is it endocrine, exocrine or both?

A

The pancreas is located between the kidneys; it is both endocrine and exocrine.

44
Q

1) Which cell type releases glucagon? When does glucagon get released?
2) What effect does glucagon have on the liver? 3) How does it affect adipose tissue?

A

1) The alpha cells in the pancreatic islets release glucagon when blood glucose gets low between meals; glucagon raises glucose.
2) In the liver, glucagon stimulates gluconeogenesis & glycogenolysis
3) Causes lipolysis of adipose tissue.

45
Q

1) Which cell type releases insulin? When does insulin get released?
2) What hormone does it antagonize?
3) An insufficiency or inaction of this hormone is the cause of what?

A

1) Beta cells in the pancreatic islets release insulin in response to high blood glucose after a meal; insulin lowers blood glucose.
2) It’s an antagonist to glucagon.
3) An insufficiency or inaction of insulin causes diabetes mellitus.

46
Q

1) Define polyuria, polydipsia and polyphagia.
2) What are the symptoms of diabetes mellitus as it relates to polyuria, polydipsia and polyphagia, and as it relates to blood tests and urinalysis?

A

1)
a) Polyuria: excessive urination
b) Polydipsia: excessive thirst
c) Polyphagia: excessive hunger
2) Diabetes mellitus causes all 3 of these symptoms because of elevated blood glucose, glucose in urine, and ketones in the urine. Polyuria is caused by the transport maximum of the kidneys.

47
Q

1) Explain Type 1 diabetes and why insulin is always used to treat type 1 but not type 2 diabetes mellitus.
2) Which type of diabetes mellitus is more prevalent?

A

1) Insulin is always used to treat type 1 diabetes mellitus because the problem is lack of insulin, whereas in type 2 diabetes mellitus the problem is insulin insensitivity.
2) Type 2 diabetes mellitus is far more common.

48
Q

1) What are risk factors for type 1? 2) What are risk factors for type 2?

A

1) Risk factors for type 1 are hereditary susceptibility; occurs when an individual gets sick and their autoantibodies attack the pancreatic beta cells.
2) Risk factors for type 2 are heredity, age (40+), obesity, and ethnicity (Native American, Hispanic, and Asian)

49
Q

Any hormone that raises blood glucose level is called a hyperglycemic hormone.
1) Can you list a hypoglycemic hormone?
2) What are some hyperglycemic hormones?

A

1) Hypoglycemic: Insulin
2) Hyperglycemic: Glucagon, growth hormone, epinephrine, norepinephrine, and cortisol

50
Q

1) Are the gonads, endocrine, exocrine or both endocrine and exocrine?
2) What other organ is similar to the gonads?

A

1) Gonads are both endocrine and exocrine
2) The pancreas is also both endocrine and exocrine

51
Q

1) Regarding the gonads, their exocrine products are whole cells, what are these cells called?
2) Their endocrine products are what?

A

1) Exocrine products: Eggs and sperm
2) Endocrine products: Gonadal hormones.

52
Q

1) The ovaries secrete chiefly estradiol, progesterone, and _________. 2) The testes secrete mainly _______________ and inhibin.

A

1) estradiol, progesterone, and inhibin.
2) testosterone, weaker androgens, estrogen, and inhibin.

53
Q

1) What are the functions of estrogen (estradiol) and progesterone?
2) What does inhibin suppress?

A

1) Development of female reproductive system and physique including adolescent bone growth, regulating the menstrual cycle, sustaining pregnancy, and preparing mammary glands for lactation
2) Inhibin suppresses FSH secretion from anterior pituitary in both sexes.

54
Q

1) Testosterone stimulates the development of what?
2) In males, by limiting ________________ secretion, inhibin regulates the rate of sperm production.

A

1) Testosterone stimulates development of male reproductive system in fetus and adolescent, and sex drive, and also sustains sperm production
2) In males, by limiting FSH secretion, inhibin regulates the rate of sperm production.

55
Q

1) What cells of the skin convert a cholesterol-like steroid into cholecalciferol using UV radiation from the sun?
2) The liver and kidneys convert cholecalciferol into what vitamin?

A

1) Keratinocytes
2) The liver and kidneys convert cholecalciferol into vitamin D.

56
Q

The kidneys secrete the hormone responsible for stimulating red blood cell production. Name kidney hormone and the target.

A

Erythropoietin targets red bone marrow.

57
Q

The kidneys secrete a hormone that stimulates production of aldosterone. Name kidney hormone and the target.

A

Renin, which targets the adrenal cortex

58
Q

Rising blood pressure stretches the heart wall and stimulates cardiac muscle to secrete atrial natriuretic peptides. What is the target and what is the action of the hormone?

A

The atrial natriuretic peptides target the kidneys to increase sodium and water excretion, which reduces blood volume and BP

59
Q

The stomach and small intestines contain enteroendocrine cells that secrete three hormones that coordinate motility and glandular secretion. Name the three hormones.

A

Cholecystokinin, gastrin, secretin

60
Q

Adipose cells secrete the hormone leptin, which has what action in the body?

A

Slows down appetite

61
Q

The placenta performs many functions during pregnancy, what hormones does it secrete and this has what action in the body?

A

Secretes estrogen, progesterone, and others. This regulates pregnancy and stimulates the development of the fetus and mammary glands

62
Q

Hormones fall into three chemical classes. What are those three chemical classes?

A

Steroids, peptides, and monoamines

63
Q

1) What are some steroid hormones and what are they derived from?
2) What are examples of peptide hormones and how are they synthesized?
3) What are some monoamine hormones?
4)Catecholamines refers to what hormones collectively?

A

1) Steroid hormones are cholesterol-derived hormones, and include sex steroids and corticosteroids.
2) Peptide hormones are chains of amino acids synthesized in the ribosome and include hormones from pituitary, hypothalamus, and insulin
3) Monoamine hormones are made from amino acids and include catecholamines, melatonin, thyroid hormone
4)Catecholamines refers to epinephrine and norepinephrine

64
Q

1) Describe the synthesis, storage, and secretion of thyroid hormone (TH). What two hormones collectively form TH? What element is required?
2) Specifically, chemically, what category class is TH in? In the body, does it behave based on its chemical classification?

A

1) Thyroid follicles absorb iodine from blood and use it to produce and release T3 and T4 when stimulated (by TSH)
2) Thyroid hormone is a monoamine, but it behaves like a steroid.

65
Q

1) Are all hormones secreted at the same rate?
2) Explain hormonal stimuli with examples using the tropic hormones.
3) Explain humoral stimuli with examples as is relates to blood-borne stimuli.

A

1) Hormones are not secreted at the same rate or a steady rate; some have daily or monthly rhythms and others are under the influence of stimuli (neural, hormonal, or humoral stimuli).
2) Hormonal stimuli is when one hormone triggers an organ to release another hormone. For example, TRH produced by the hypothalamus promotes the production of TSH by the anterior pituitary, which promotes the thyroid to produce TH.
3) Humoral stimuli refers to blood-borne stimuli. For example, high blood glucose stimulates the release of insulin, and low blood calcium stimulates the release of parathyroid hormone

66
Q

1) Which of the three chemical classes are considered hydrophilic, which are hydrophobic? 2) Do they mix with blood plasma? What hormone is the exception?

A

1) Steroids are hydrophobic, most monoamines and peptides are hydrophilic.
2) Steroids do not mix with blood plasma, monoamines and peptides do (thyroid hormone is the exception to this rule).

67
Q

1) If a hormone is hydrophobic, what transport proteins help the hormones get around the body?
2) Define half-life. 3) Which hormones have a longer half-life and why?

A

1) Albumins and globulins help transport hydrophobic hormones.
2) How long it takes for half of the chemical to degrade.
3) Bound (aka hydrophobic) hormones typically have a longer half-life because they’re protected from liver enzymes and kidney filtration.

68
Q

1) What does the cell have to have in order for the hormone to stimulate it?
2) Where is that going to be located?

A

1) The cell must have a receptor for that hormone. 2) Receptors can be found embedded in the plasma membrane, in the cytoplasm, or in the nucleus.

69
Q

Receptor–hormone interactions are similar to enzyme–substrate interactions. Unlike enzymes, receptors do not chemically change their ligands; they do, however, exhibit specificity and saturation.
1) Specificity means what?
2) Saturation is what?

A

1) They have a specific receptor for each hormone
2) They’re saturated when all of the receptors are occupied by molecules.

70
Q

Peptides and catecholamines are hydrophilic and cannot penetrate into target cells, so what must they bind to? Where is it located?

A

They bind to receptors on the surface of the cell and activate intracellular processes through second messengers

71
Q

1) Steroid hormones and thyroid hormone enter the target cell, so what they must bind to is sometimes in the cytoplasm, but more commonly is found in the __________
2) What is the function of steroid hormones and TH in a target cell? Steroid and thyroid hormones typically require how long in order to show an effect and why?

A

1) Steroid hormones and thyroid hormone enter the target cell, so what they must bind to is sometimes in the cytoplasm, but more commonly is found in the nucleus.
2) They influence the expression of genes in the target cell, but they take several hours to days to show effect due to lag for protein synthesis

72
Q

Thyroid hormone in the T4 form has little metabolic effect, but in the target cell cytoplasm, an enzyme converts T4 to the more potent T3. Once T3 enters the target cell nucleus and binds to receptors, what is one gene that you know it activates?

A

The sodium-potassium pump gene.

73
Q

What is signal amplification?

A

The concept that a small stimulus can have a huge effect.

74
Q

1) Target cells can modulate their sensitivity to a hormone by doing what? What happens in terms of sensitivity?
2) Can you give an example of why you might need to up-regulate or down regulate receptors?

A

1) Up-regulating (increasing the number of receptors) and down-regulating (decreasing the number of receptors)
2) It’s used to adjust target cell sensitivity, such as when a hormone is being chronically over or under produced.

75
Q

1) What are synergistic effects?
2) Can you list an example of a synergistic effect?
3) What are permissive effects?
4) Can you list an example of a permissive effect?

A

1) Multiple hormones act together for greater effect
2) Ex: Synergism between FSH and testosterone on sperm production
3) One hormone enhances the target organ’s response to a second later hormone
4) Ex: Estrogen prepares uterus for action of progesterone

76
Q

1) What are antagonistic effects?
2) Can you list examples of antagonistic effects?

A

1) One hormone opposes the action of another
2) Examples: Insulin lowers blood glucose and glycogen raises it, PTH raises blood calcium and calcitonin raises it

77
Q

1) Hormone clearance occurs when hormones are taken up and degraded by what two organs?
2) What two ways is it excreted?

A

1) By the liver or kidneys.
2) Excreted in bile or urine